Will the EPA Abandon the Science of Risk?

A prevailing take-away message from last month's March for Science was that President Trump and his Environmental Protection (EPA) Administrator, Scott Pruitt, are in the process of dismantling critical science-based rules that were put in place to protect nature. With nature left unprotected, they argued — or, rather, chanted — we'll be exposed to dangerously contaminated air and water, and the environment will be devastated.

Given the alleged consequences, careful consideration of how new leadership will carry out the EPA's congressionally mandated obligations is certainly warranted. Unfortunately, the Bill Nyes of the world claim the mantle of science, while at the same time seeking to silence and disparage those who challenge their assertions. This tactic is antithetical to the spirit of scientific inquiry.

Science, it turns out, is under attack from those who claim to be defending it. At the forefront of this trend, driven by environmental groups, is opposition to the science of risk analysis.

Risk analysis is the well-established field that relies on the distinction between two important concepts: "hazard" and "risk." A hazard is something that has the capacity to cause harm, such as water, which can cause drowning. A risk is the probability that the harm will actually happen under certain conditions, including exposure.

Environmental activists prefer that we disregard risk assessment and instead adhere to the European-style precautionary principle. This principle calls for the banning of chemicals, for instance, even when a risk assessment finds an extraordinarily low risk. Often, the supposed "risk" is due to uncertainty about the scientific findings. The problem? Certainty is always more or less present in science.

All eyes will be on the EPA as it implements the "Frank R. Lautenberg Chemical Safety for the 21stCentury Act," also known as the Toxic Substances Control Act, or TSCA. President Obama signed TSCA last year after Congress passed it with wide bipartisan support. It requires the EPA's regulatory approach to incorporate risk assessment into its regulatory approach.

In November, the EPA identified the first 10 chemicals to be evaluated under the law. The chemicals, which include aasbestos and 1,4-Dioxane, were chosen not only because of the hazards they pose — or their capacity to do harm to humans or the environment — but because of their potential for relatively high exposure. In other words, they were picked because of the risks they pose.

Keen followers of these issues will be watching to see whether the Trump administration buys into precautionary logic or sticks to its promise to "protect our environment without harming America's working families." Is it even possible to protect simultaneously the environment, the jobs of America's working families, and all of us who benefit from the wondrous array of products available as a result of modern chemistry? And if so, how is the proper balance achieved?

A completely laissez-faire approach to chemical regulation would certainly fail to protect the environment. At the other extreme, the precautionary principle would remove from the market products that enhance our lives, and even improve safety. Does achieving the proper balance require picking some happy medium between the two — either through random chance or political means?

No. To maximize human and environmental safety as well as maintain access to products, we must use the science of risk assessment to guide us. This is why Congress required EPA to use this approach.

Consider how these vastly different approaches have played out over the last few years as regulators wrestled with the alleged environmental hazard of a particular class of silicones, Siloxanes D4 and D5. Because of their unique properties — which include a slippery feel and stability in a range of temperatures — siloxanes are used in a wide range of applications, from energy efficient LED lights, to medical and personal care products, such as soaps and shampoos.

In Europe, as a result of the application of the precautionary principle, consumers will no longer have access to shampoos that contain these Siloxanes. In their quixotic effort to create a risk-free world, E.U. regulators relied on unrealistic and flawed models to create enough doubt about environmental impact to justify a ban on certain personal use products.

As Christine F. Solbakken put it in the Norwegian Institute for Air Research:

"The proposal is partly based on the presumption that siloxanes bioaccumulate in aquatic food chains ... However ... even if ECHA has concluded that D4 and D5 are bioaccumulative, this decision was largely based on laboratory-studies, while field-studies of bioaccumulation are still contradicting each other."

Contrast this extreme approach with the one taken by Canada's highly esteemed environmental protection agency, which considered the same chemicals.

The Environment and Climate Change Canada (ECCC), using real world exposure information, decided to minimize exposure to a level that didn't degrade the environment, requiring monitoring from certain industrial sources. In other words, the ECCC didn't just consider the hazard, they also considered the risk. As a result, Canada did not ban consumer use, but, instead, took steps to reduce environmental exposure from only a narrow group of industrial sources that were potential problems.

With regard to D4, ECCC regulators found that the chemical "is entering or may be entering the environment in a quantity or concentration or under conditions that have or may have an immediate or long-term harmful effect on the environment or its biological diversity." But instead of banning its use, consistent with their risk management approach, they required a significant reduction of "D4 releases to the aquatic environment" and encouraged the use of alternatives to reduce or minimize risks.

On D5, Canada's regulators did something even more practical. Recognizing industry objections to the E.U.-style modeling approach, which ECCC initially used for D5, the Board of Review took real-world exposures of D5 into account. Then they did what all good scientists should be prepared to do: they reversed course after finding that new, more accurate data conflicted with their initial findings. In light of the improved information, the ECCC regulators wrote that "it is virtually impossible for Siloxane D5 to occur in any environmental matrix at concentrations sufficient to produce harm to the environment."

February 29, 2012 was a rare day indeed. D5, a chemical originally considered toxic by ECCC, was removed from the Canadian government's list of toxic substances. This represents a triumph of risk assessment over the political ideology of the precautionary principle. In short, Canada was able to protect the environment while still permitting the use of a chemical that betters our lives.

Good science allows us to have the best of both worlds: protection and progress. The EPA should follow suit and implement TSCA's requirement to utilize risk assessment, even over the politically charged howls of environmental activists who claim a monopoly on science, even when their approach is anything but scientific.

Jeff Stier is a Senior Fellow at the National Center for Public Policy Research in Washington, D.C., and heads its Risk Analysis Division.